Exam 6: Independent Groups Designs

The natural groups design represents an illustration of the general research approach that is called

The researcher should

A researcher randomly assigns one classroom to a new teaching method and a second classroom to the control condition (the regular teaching method).This researcher faces the potential problem of confounding due to

When participants begin an experiment but fail to complete it,the internal validity of the experiment can be threatened.Which of the following types of subject loss poses the most serious threat to internal validity?

In order to conduct an experiment more efficiently a researcher tests groups of participants in several small groups.The sizes of the groups differ because of differences in participants' availability at different times.The different sizes of the groups represent a potential

Which of the following conditions would lead you to recommend against the use of a matched groups design and in favor of a random groups design?

Which of the following is not an advantage of using measures of effect size?

A researcher has manipulated only one independent variable at two levels,has held constant as many other variables as possible and has balanced individual differences by using random assignment.The researcher is likely to be able to claim that the independent variable caused the observed changes in the dependent variable because the experiment is

In what situation is it argued that external validity is irrelevant?

Explain how the procedures for conducting a matched groups design and a natural groups design differ from the random groups design.

Subject loss (attrition)poses a problem for a random groups design because

Which of the following is the most critical problem in drawing causal inferences based on the natural groups design?

Random assignment to conditions works to balance participants' individual differences across conditions of the experiment by

When conducting an experiment using the matched groups design,the preferred pretest task (matching task)is

When we conclude that an experiment does not provide sufficient evidence to reject the null hypothesis when,in fact,an independent variable does produce an effect,the inferential statistics problem is called a

Identify and briefly define the three primary types of control that are used in experiments.

In addition to creating groups of equal size,an advantage of block randomization is that it

A Type I error occurs when the null hypothesis is really true and we claim

To differentiate experiments involving individual differences (subject)variables and those involving manipulated independent variables,those experiments involving individual differences (subject)variables are called

Identify the two major reasons why psychologists conduct experiments.